When Jack and Annie got back from their adventure in Magic Tree House #7: Sunset of the Sabertooth, they had lots of questions. What was it like to live in the Ice Age? How did early humans stay warm enough to survive? Who made the first cave paintings? What happened to saber-toothed cats and woolly mammoths?

When Jack and Annie got back from their adventure in Magic Tree House #16: Hour of the Olympics, they had lots of questions. What did the ancient Greeks wear? What did they do for fun? Where were the very first Olympics held? How are our modern Olympics similar to the ancient Olympics?